Fix #12199. Handle iteration over inherited properties in oldIE. Close

gh-1196.

AUTHORS.txt

@@ -162,3 +162,4 @@ Jean Boussier <jean.boussier@gmail.com>
 Adam Coulombe <me@adam.co>
 Andrew Plummer <plummer.andrew@gmail.com>
 Dmitry Gusev <dmitry.gusev@gmail.com>
+Brandon Johnson <bjohn465+github@gmail.com>

src/core.js

@@ -453,6 +453,8 @@ jQuery.extend({
 	},
 
 	isPlainObject: function( obj ) {
+		var key;
+
 		// Must be an Object.
 		// Because of IE, we also have to check the presence of the constructor property.
 		// Make sure that DOM nodes and window objects don't pass through, as well
@@ -472,10 +474,16 @@ jQuery.extend({
 			return false;
 		}
 
+		// Support: IE<9
+		// Handle iteration over inherited properties before own properties.
+		if ( jQuery.support.ownLast ) {
+			for ( key in obj ) {
+				return core_hasOwn.call( obj, key );
+			}
+		}
+
 		// Own properties are enumerated firstly, so to speed up,
 		// if last one is own, then all properties are own.
-
-		var key;
 		for ( key in obj ) {}
 
 		return key === undefined || core_hasOwn.call( obj, key );

src/support.js

@@ -141,6 +141,13 @@ jQuery.support = (function( support ) {
 	div.cloneNode( true ).style.backgroundClip = "";
 	support.clearCloneStyle = div.style.backgroundClip === "content-box";
 
+	// Support: IE<9
+	// Iteration over object's inherited properties before its own.
+	for ( i in jQuery( support ) ) {
+		break;
+	}
+	support.ownLast = i !== "0";
+
 	// Run tests that need a body at doc ready
 	jQuery(function() {
 		var container, marginDiv, tds,

test/unit/core.js

@@ -296,7 +296,7 @@ test("type", function() {
 });
 
 asyncTest("isPlainObject", function() {
-	expect(15);
+	expect(16);
 
 	var pass, iframe, doc,
 		fn = function() {};
@@ -330,6 +330,16 @@ asyncTest("isPlainObject", function() {
 	// Again, instantiated objects shouldn't be matched
 	ok( !jQuery.isPlainObject(new fn()), "new fn" );
 
+	// Make it even harder to detect in IE < 9
+	fn = function() {
+		this.a = "a";
+	};
+	fn.prototype = {
+		b: "b"
+	};
+
+	ok( !jQuery.isPlainObject(new fn()), "fn (inherited and own properties)");
+
 	// DOM Element
 	ok( !jQuery.isPlainObject( document.createElement("div") ), "DOM Element" );
 

test/unit/support.js

@@ -80,7 +80,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":true,
 			"ajax":true,
 			"cors":true,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": false
 		};
 	} else if ( /opera.*version\/12\.1/i.test( userAgent ) ) {
 		expected = {
@@ -113,7 +114,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":true,
 			"ajax":true,
 			"cors":true,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": false
 		};
 	} else if ( /msie 10\.0/i.test( userAgent ) ) {
 		expected = {
@@ -146,7 +148,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":true,
 			"ajax":true,
 			"cors":true,
-			"clearCloneStyle": false
+			"clearCloneStyle": false,
+			"ownLast": false
 		};
 	} else if ( /msie 9\.0/i.test( userAgent ) ) {
 		expected = {
@@ -179,7 +182,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":true,
 			"ajax":true,
 			"cors":false,
-			"clearCloneStyle": false
+			"clearCloneStyle": false,
+			"ownLast": false
 		};
 	} else if ( /msie 8\.0/i.test( userAgent ) ) {
 		expected = {
@@ -212,7 +216,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":false,
 			"ajax":true,
 			"cors":false,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": true
 		};
 	} else if ( /msie 7\.0/i.test( userAgent ) ) {
 		expected = {
@@ -245,7 +250,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"submitBubbles": false,
 			"tbody": false,
 			"style": false,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": true
 		};
 	} else if ( /msie 6\.0/i.test( userAgent ) ) {
 		expected = {
@@ -278,7 +284,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":false,
 			"ajax":true,
 			"cors":false,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": true
 		};
 	} else if ( /5\.1\.1 safari/i.test( userAgent ) ) {
 		expected = {
@@ -311,7 +318,8 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":true,
 			"ajax":true,
 			"cors":true,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": false
 		};
 	} else if ( /firefox/i.test( userAgent ) ) {
 		expected = {
@@ -344,13 +352,14 @@ testIframeWithCallback( "box-sizing does not affect jQuery.support.shrinkWrapBlo
 			"reliableHiddenOffsets":true,
 			"ajax":true,
 			"cors":true,
-			"clearCloneStyle": true
+			"clearCloneStyle": true,
+			"ownLast": false
 		};
 	}
 
 	if ( expected ) {
 		test("Verify that the support tests resolve as expected per browser", function() {
-			expect( 30 );
+			expect( 31 );
 
 			for ( var i in expected ) {
 				if ( jQuery.ajax || i !== "ajax" && i !== "cors" ) {